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arXiv · 1510.04749

Intersite electron correlations in a Hubbard model on inhomogeneous lattices

Nayuta Takemori·Akihisa Koga·Hartmut Hafermann
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Abstract

We study intersite electron correlations in the half-filled Hubbard model on square lattices with periodic and open boundary conditions by means of a real-space dual fermion approach. By calculating renormalization factors, we clarify that nearest-neighbor intersite correlations already significantly reduce the critical interaction. The Mott transition occurs at U/t~6.4, where $U$ is the interaction strength and t is the hopping integral. This value is consistent with the quantum Monte Carlo results. This shows the importance of short-range intersite correlations, which are taken into account in the framework of the real-space dual fermion approach.

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Nayuta Takemori, Akihisa Koga, Hartmut Hafermann. 2015-10-16. Intersite electron correlations in a Hubbard model on inhomogeneous lattices. https://doi.org/10.1088/1742-6596%2F683%2F1%2F012040

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